Simon Cowell -- The Ex Whisperer


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Simon Cowell
is the new Winston Churchill -- last night he took his current girlfriend AND his ex-fiancee out to dinner ... at the same time ... and somehow, it didn't end in World War 3.


Simon treated baby mama-GF Lauren Silverman and ex-fiancee Mezhgan Hussainy to a fancy dinner at Miami's Prime Fish, where they ate outside and basked in Florida's stifling humidity.


The three later emerged from the restaurant without a single scratch.


Guess Mezhgan wasn't lying when she said she was happy for Simon and his new girl -- the $8 million mansion Simon gave her probably didn't hurt either.


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